<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
		<button>测试1</button> <br />
		<button>测试2</button> <br />
		<button>测试3</button> <br />
	</body>
	
	<script>
		let buts = document.getElementsByTagName("button")
		Array.from(buts).forEach(function(item, index){
			console.log(item)
		})
		
		let arr = Array.of(1, "hello", true)
		console.log(arr)
		let arr2 = [2, 5, 8, 4, 7]
		let result = arr2.find(function(item, index){
			return item > 4
		})
		console.log(result)
	</script>
</html>
